JPH0133258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a component having a large hole, and particularly to a manufacturing technique that utilizes nearly 100% of the material of a flanged component whose outer periphery is close to that of the hole.

Conventionally, parts with large holes, such as the fluid machine outlet part shown in Figure 1 and the mouth ring of a fan shown in Figure 2, and which had a stretch flange molded part 1 or a contracted flange molded part 2, were made as shown in Figure 3. As shown in the figure, rings such as rectangular plates 4 and 5 were cut out and used as raw materials. However, in this case, the corner 6
Since the part shown in and the hole 7 were scrapped, the material for the ring part 5 was less than 50% of the material for the rectangle 4, resulting in a large waste of material. In addition, the end portions of the stretch flanged portions have a thinner wall thickness and are prone to cracking, and the end portions of the shrink flange portions have thicker walls than necessary, resulting in wasted material.

An object of the present invention is to manufacture parts having such large holes, especially parts having shapes in which the hole and its outer circumference are close to each other, at a yield of nearly 100%.

A rolling and bending process in which the band member is rolled to create a difference in thickness in the width direction to form a ring-shaped material, and a ring-shaped material is formed with a cut of the required length after the rolling and bending process. A cutting process, a process of joining the cut end surfaces after the cutting process to form a closed ring-shaped material, and shrinkage flange forming or shrinkage flange forming in which a flange is formed in a direction to reduce the outer circumference dimension of the closed ring-shaped material, or the inner circumference dimension is reduced. By creating parts with large holes from strip material using a manufacturing method for parts with large holes, which consists of a stretch flange forming process in which the flange is formed in the direction of increasing the size, nearly 100% of the material can be utilized. This is what I did.

An embodiment of the present invention will be described below with reference to FIG.
FIG. 4 shows a line for manufacturing the parts shown in FIG. The coiled strip 8 is an uncoiler 9
It is sent to a rolling bending machine 11 via a switch 10 that adjusts the slackness of the unwound film. In the rolling bending machine, the strip passes through a leveler 12, rolling rolls 13, and guides 14, and is bent into a ring shape as shown in 15.
The circumferential length is measured by an encoder 16 and cut into a ring 18 of the required length by a flying cutter 17. The cut portion is cut into a shape as shown in FIG. 5 by taking out the scrap 20, and is mated as shown in FIG. 6 by a spot welding machine shown at 21 in FIG. 4 and spot welded at a point 22. The material joined in a ring shape by spot welding is pressed to the outer circumferential side (hereinafter referred to as "outside") by the press shown in FIG. 422, like the parts shown in FIG. A stretch flange forming part 1 is formed on the inside (referred to as the inside). Generally, the lap portion 19 is not spot-welded, but is cut into a straight line, and the entire joint line is welded and then formed, but the joining method is not limited to welding. In the case of the production line shown in Fig. 4, in order to save welding time, one spot weld 22 is used as shown in Fig. 6.
Since the parts 23a and 23b are only butted together, if the inner side of the forming boundary shown in FIG. 6 24a is stretched and flanged, 23a
There is a drawback that the part opens. Therefore, when rolling and bending is performed using the rolling and bending machine 11 shown in FIG. During stretch flange forming, these wrinkles are smoothed out during forming.
This prevents section 3a from opening. If you take the method of stretch flange forming while smoothing out these wrinkles, 2
Even if part 3a is welded, it is possible to prevent that part from cracking, and if the welded part is strong, the stretch flange height can be made higher than the limit of stretch flange forming using general plate materials.

In addition, as shown in Fig. 7, the cross section of the ring that has been rolled and bent maintains the original thickness at the inner side 26a, and the outer side 26a retains the original thickness.
b is thinner than that, so if molding is performed there, the inner stretch flange part 1 will become thinner,
Since the outer shrinkage flange portion 2 becomes thicker as it goes forward, there is also the advantage that changes in thickness cancel each other out, resulting in a product with smaller changes in overall plate thickness than those made from a general plate.

FIG. 8 shows a raw material ring according to another embodiment, which was rolled on one side only at the section 27.
The part is simply stretched out and is used to make parts with large square holes.

FIG. 9 shows an example in which the shape of the inner hole is not similar to the outer hole, and the molding is performed after punching out the part 29. In this case as well, the material yield can be greatly improved compared to removing the material from all of the inner hole.

According to the present invention, parts with large holes, especially parts with large holes with flanges, can be manufactured from strips, so that scrapping of the hole parts can be saved and material costs can be significantly reduced. Furthermore, according to the method of the present invention, the difference in the maximum and minimum thickness of parts with large holes, especially those with large flanges, can be made smaller and lighter than when they are manufactured from general flat plate materials. There is also the effect of Furthermore, by molding a material with wrinkles generated on the inside, the forming limit of stretch flange molding can be greatly improved.

[Brief explanation of drawings]

FIGS. 1 and 2 are longitudinal cross-sectional views of parts targeted by the present invention;
Fig. 3 is a plan view showing the material collection in the conventional method, Fig. 4 is an external view of manufacturing equipment according to an embodiment of the present invention, and Fig. 5
6 is a plan view of a joint portion of an embodiment of the present invention; FIG. 7 is a vertical sectional view of an embodiment of the present invention; FIG. FIG. 9 is a plan view of an intermediate product according to another embodiment of the present invention. 1...Stretch flange part, 2...Shrink flange part, 3...Stretch flange part, 4...Square material, 5
... Ring-shaped material, 6 ... Scrap, 7 ... Scrap, 8 ... Strip coil, 9 ... Uncoiler, 10 ... Switch, 11 ... Bending device, 12
... Leveler, 13 ... Roll, 14 ... Guide, 15 ... Material bending section, 16 ... Encoder, 17 ... Cutter, 18 ... Ring, 19 ...
... Cutting line, 20 ... Scrap, 21 ... Welding machine, 22 ... Press, 23a, 23b ... Butt line, 24a, 24b ... Molding boundary line, 25 ...
Wrinkles, 26a...inner end surface, 26b...outer end surface.

Claims (1)

[Scope of Claims] 1. A rolling bending process in which a ring-shaped material is obtained by rolling a strip member with a difference in thickness in the width direction, and a cut of a required length after the above-mentioned rolling bending process. A cutting process to make a certain ring-shaped material, a process to join the cut end surfaces after the cutting process to form a closed ring-shaped material, and a shrinkage process to form a flange in a direction to reduce the outer circumferential dimension of the closed ring-shaped material. A method for manufacturing a part having a large hole, comprising a step of performing flange forming or stretch flange forming in which the flange is formed in a direction that increases the inner circumference dimension. 2. In the rolling and bending process, wrinkles are formed on the inner peripheral side of the ring-shaped material, and the inner peripheral end surface shape is wavy in the thickness direction, and in the stretch flange forming process, the wrinkles are smoothed out to form a flange. A method for manufacturing a component having a large hole according to claim 1.